Turn-over devices for use in the steel industry are known and usually comprise a four wheel carriage running on two rails arranges transverse to the path of the conveyor. On the carriage, two tongues are mounted, each of them actuated by a hydraulic cylinder and an integral part of a two pinion shaft which gears in two racks, these also actuated by two other hydraulic cylinders. The carriage is advanced on the tracks by another hydraulic cylinder, independent of the first four.
The slab material to be turned over is engaged by the two tongues driven by the first two cylinders, turned over through 180.degree. with the help of the other two cylinders which drive racks and pinions, and the fifth cylinder moves the carriage to the desired position where the slab is to be let down.
The drawbacks of these devices lie in the complexity and excessive sophistication of the structure; three distinct drives with five hydraulic cylinders requiring their own hydraulic station and the highly skilled personnel required to operate the device. Also, the device is not integrated physically into the conveyor line in which it serves and therefore occupies a large space on either side of the conveyor since it must move transversely thereto.